1. Field of the Invention
The present invention relates to identifying molecular structures and cell types in walls of a body lumen in animals; and in particular to fluorescent imaging of cell types in walls of a body lumen for diagnosis or therapy, such as in vivo therapy based on selective destruction of labeled tumor cells. The invention has application to the diagnosis and treatment of intestinal cancer and colon cancer, among other pathologies and syndromes.
2. Description of the Related Art
Cancer of the gastrointestinal (GI) tract is easily treated if detected early. Consequently a great deal of activity has been expended in developing systems to inspect the GI tract for early signs of cancer. One of the first significant advances was the endoscope, which allows a doctor to inspect portions of the GI tract with a miniaturized light source at a probe end of a coherent bundle fiber optic cable. Reflected light beam images are returned through the fiber optic cable for detection by an external digital camera and display on an external monitor or for recording on an external video recorder or both.
While suitable for inspection of the esophagus, stomach and portions of the large intestine, the endoscope is neither capable of inspecting some portions of the large intestine (colon) nor capable of inspecting most of the small intestine.
In recent years, swallowable capsules containing miniaturized optical, digital camera and radio transmission systems have been developed along with complementary external monitoring systems for inspecting the small intestine. For example, one capsule and monitoring systems is marketed as M2A by Given Imaging Ltd. of Yokneam, Israel and another is marketed as NORIKA from RF SYSTEM Lab. of Nagano City, Japan. At the time of this writing, these systems are described on the World Wide Web at internet domains givenimaging.com and rfnorika.com, respectively. Elements of these systems are described in several patents, including U.S. Pat. No. 5,604,531 by G. V. Iddan and D. Sturlesi issued Feb. 18, 1997 (hereinafter Iddan I), the entire contents of which are hereby incorporated by reference as if fully set forth herein.
The capsule is swallowed by a patient and makes its way into the small intestine. As the capsule is pushed through the small intestine by peristalsis, it lights the wall of the intestine and captures images of the wall with the camera system and transmits those images to the monitoring unit outside the patient. The monitoring unit includes radio frequency (rf) receivers around the torso of the patient, a processor to interpret the signals received, a recorder to record the interpreted imagery, and a display to present the image to a technician or medical doctor. Because it can take the capsule about eight hours to traverse the intestinal tract, the data is often recorded first and the technician reviews a videotape replay that can be viewed in a shorter time, on the order of an hour.
While representing a great advance in imaging the morphology of the small intestine and the upper large intestine (upper colon), as well as other body openings (body lumen), there are still some deficiencies with the prior art capsule systems. Reflectance imaging such as that performed by both of the Givens and Norika systems monitor the morphology of the interior walls of the lumen i.e. shape in the form of growths or protrusions of the wall. In the earliest stages, some cancer cells and pre-cancerous cells do not form structures that can be distinguished by morphology from other structures found on the cell wall. In the more advanced stages, when tumors are apparent by their morphology, the prior art capsule systems can not distinguish between a tumor mass containing dying cells that are responding to treatment, and a tumor mass with viable cells that are resisting treatment or are continuing to grow. In other diseases of cells in the intestinal wall, abnormal cells, which otherwise appear morphologically the same as normal cells, are performing different functions and generating or ingesting different molecules, including different proteins. For example, such diseases include gastrointestinal motility, ischemia and protein-losing disorders. Therefore, existing capsule systems can not distinguish some significant disease-related types and functions of cells making up the structure of the walls.
Based on the foregoing, there is a clear need for techniques that determine cell types and functions in the walls of the small intestine or the upper large intestine or both.
In general, there is a need for techniques that determine cell types and functions in the walls of a body lumen, including the GI tract, a sinus passage, and a large blood vessel, among others.